I took the car out to the track for the first time and was a little dissapointed but I think something in my combo is holding the car back. It ran 12.2 @ 115. 60 ft. was a ridiculous 2.1 on et streets.

Here is my mods. Ptk 351 street kit with pt67s, Victor Jr 70cc heads, super victor efi intake w/wilson manifolds upper plenum, 4.10 gear, C6 and shift kit w/stock converter, stock computer, fmu, total fuel pressure is 80psi at about 11psi boost.

I can't build boost at the line due to the converter, but it spools quickly and pulls very hard after the 60ft through 1st and 2nd, 3rd does'nt feel as good. I knew this transmission would hurt it but this seems really slow.

Help please.

 

your converter and gear are wrong. I dont know much about converters for turbo cars, i'll let someone else lead you in the right direction on that. But a 4.10 gear is WAY to steep for a turbo car. Go with a 3.27, but if i were to make a educated guess on what kind of converter you should get, i would say go with a 2600-2800 stall.

 

I know that you say it is slow but with such a poor 60', that thing would have been well into the 11's with a 1.70 or better 60'. I also think that with that motor size that the turbo may become a retriction as well. What is the turbine housing size and is it a T3 or T4 flange. You may be runnign too much gear as well. What size injectors? Do you use a wideband of any kind? As the other gentelman said, the stock converter may very well be a big issue too.

 

You didn't say what injectors you are running but 80 psi of fuel pressure seems like alot with 11 psi boost.

 

Thanks guys.

To reply to your other questions the turbo is pt67s, T04s cover, 67mm 63 trim gt comp wheel 76 p trim turbine wheel A/R .81.
42 lb. injectors. I don't have a wide band on it or a chip. I'm trying to keep it fat right now. Don't want to blow it up. 8 deg. base timing.

Also this might be a factor. I'm not positive what my compression ratio is. It had 69' DOOE heads on it, and when I went turbo I swithched to 70cc and did'nt change pistons. I'm thinking it's around 8:1 or less. I get 120 psi on compression test.

 

true, that with a better 60' he would have been in the 11's, but his MPH is way low. My Incon 800tti car (god rest it soul) with a completely stock longblock went 126 on 255 BFG DR's with 12 psi.

 

Yeah, you're right but you had a matched system. His "ONE" turbo is too small and he has a 4.10 gear which both are probably slowing the car down on the back side. That 351 needs to "BREATHE" man. The turbine side being a P-trim and more than likely a On-center housing makes it worse. It still will go 11's but your MPH may not make it over 120 MPH with that turbo.

 

I'd say a .96 housing, 3.27 gears, and a converter would really help.

 

Reasons:

Too much gear

Not enough converter

Turbo too small

Lack of proper tuning

Correct these things and it will go 9's.

 

Whats up with that fuel pressure it sounds a bit high with only 11 lbs of boost, but just to chime in here those gears are way too high, definately go down to the 3.27's and get a better stall converter depending on your cam that your using, if its a relatively small cam you could run like a 3500 stall coverter and get a lock up on that AOD and you should be good (not sure if your using an AOD or not). Also that turbo may be a bit to small for that motor, I also have a 351W roller motor with the vic jr. 70cc heads and the super vic jr. carb manifold converted to EFI with a coast high elbow, what pistons are you running??? and what thickness is your head gasket???? Also what size throttle body you got one there?????? I think if you got a converter around 3500 and a 3.27 rear gear and a computer tune you will see a big time improvement on your ET. Let us know what else is on your set up so we can help more.

 

Not to Hi-jack the thread. but I have the same turbo but with a tang. .98 housing. I thought this turbo could support 800 hp?

I do agree with everyone the fuel pressure seems high, your stall will make a big difference, the C6 are known to rob a lot of power (I had one), and your housing may be too small for the combo, gearing is way to high at least 3.55s or like everyone else says 3.27s.

good luck

dave ross

 

you are running an FMU and 42# injectors? ditch the FMU, set fuel pressure to 42# line off, set timing to 20*'s total and run it again. What were your 1/8th mile numbers?

4.10s won't hurt the cars ability to haul ass in the 1/8th

 

All the info sounds like good advice. I will definetly lower that fuel pressure. My plugs look very rich. I would like to have the money for a glide or c-4. What do you guys think about getting my broken tko built by pro motion.

Also I know my engine needs gobs of air seeing that it is a windsor with vic jrs and a super vic intake but that turbo should support 650 to 700 at the tires I've been told. Anyway I would like to go mid to high 10's with this turbo. It's brand new.

 

if your gonna invest money in a transmission get a glide built, c4's can be tricky sometimes I broke a few of them that were built by very reputable companies. I have yet to break my glide. I would not really get your tremec redone I think you'll just have a hard time getting the car to hook and you'll probably go through the phases of breaking parts with a tremec. I have been through a ton of different transmission set ups and the powerglide is hands down the best transmission to run behind a turbo car. What type of pistons are you using with those heads Im curious what your compression ratio is???

 

I bought the car and it had 69' DOOE heads on it. I have'nt touched the short block. The guy said it had 8:1 because it had a roots blower at one time. I don't think I believe him. If it was really 8:1 with those 62cc heads then it's like close to 7:1 with 70cc heads. I honestly don't know what pistons they are. They were'nt really a dish but they had very large valve reliefs. It is a 69' block with a stock crank and rods.